Aquatic propulsion system



Oct. 22, 1968 R. 1.. MELA AQUATIC PROPULSIQN SYSTEM 2 Sheets-Sheet 1 Filed July 27, 1966 n k r.

INVENTOR. RICHARD L ME LA ATTORNEYS 2 Sheets-Sheet 2 Filed July 27, 1966 2 3 E 3 L .wlw E], ,2 ow E I g we wow I w n l lmw W ND mww in 3% mm 3 vm N.

INVENTOR. RICHARD L. MELA fiMAM W ATTORNEYS United States Patent 3,406,653 AQUATIC PROPULSION SYSTEM Richard L. Mela, Arlington, Mass., assignor to The Powermite Corporation, Arlington, Mass. Filed July 27, 1966, Ser. No. 568,257 9 Claims. (Cl. 11570) ABSTRACT OF THE DISCLOSURE A powered floatboard is constructed with a substantially solid hull. An openly exposed power unit is seated in a recess formed in the upper surface of the hull. The recess is shaped to form a sump and a pump operating directly off the power unit continuously removes water from the sump. An air intake connected directly to the power unit is shielded from spray and splashing water and has a filter which is water-impervious, but air-pervious.

This invention relates to a powered aquatic craft and more particularly to the arrangement of a powered floatboard in which the engine is relatively openly exposed to water. The absence of a waterproof or like protective housing for the engine enables the craft to be inexpensive. It also facilitates making the craft compact and lightweight. However, omitting such a housing introduces several problems for which the present invention provides economic solutions.

The prior art is replete with powered aquatic craft in which a housing seals or substantially fully protects the engine from water. However, such a housing adds materially to the cost of the craft, and often also adds to the weight or bulk. This is particularly true with prior small craft for propelling one person who is substantially openly exposed to the water.

Further, recreational aquatic craft often employ a pump to bail bilge water from within the hull. These pumps have heretofore been fairly costly. For example, many require a relatively complex drive linkage between the engine and the pumping mechanism, which is often a multielement assembly.

It is an object of the present invention to provide a low cost powered aquatic craft. Further, it is an object to provide a compact and lightweight construction for a powered fioatboard.

In particular, it is an object of the invention to provide a relatively low cost construction of a fioatboard powered with an internal combustion engine that is not sealed from the water and yet is guarded from disablement by water. Further, it is an object to provide such a powered fioatboard having means that relatively freely passes air to the air intake of the engine but blocks Water from entering therein.

Another object of the invention is to provide an improved bailing pump for craft of the above character. Specifically, it is an object of the invention to provide a bailing pump characterized by low cost. Further, the pump should be simply constructed. It is also an object that the pump be highly reliable.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts exemplified in the constructions hereinafter set forth, and the scope of the invention is indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

3,406,653 Patented Oct. 22, 1968 FIGURE 1 is a top plan view of a powered floatboard embodying the invention;

FIGURE 2 is a side elevation view, partly broken away, of the powered board of FIGURE 1; and

FIGURE 3 is a transverse cross-section view of the floatboard of FIGURE 1 taken along line 3-3 of FIG- URE 2.

In accordance with the invention, the engine of the present aquatic craft is seated in an enclosure recessed in a fioatboard-like hull. The engine and associated drive elements are mounted fairly low on the floatboard so as not to block the users vision and to maintain the height of the craft small. However, due to this low disposition of the engine, water that invariably enters the enclosure can not merely be drained out. Accordingly, a novel bailing pump is arranged in a sump in the enclosure to expel the water. The pump has a single pumping element normally driven directly from the engine shaft.

Further, the air intake on the engine is fitted with means that relatively freely admits air to the engine but elficiently blocks water. Thus, there is little likelihood that water will enter the carburetor.

With this arrangement, the engine continues running and propelling the fioatboard even when it is operated in the midst of surf or splashing.

More specifically, as shown in FIGURES 1 and 2, a powered fioatboard 10 embodying the invention has a highly buoyant hull 12 of expanded polystyrene or other highly buoyant material or construction. The user typically reclines on the craft with his trunk resting on the hull behind a power unit 14 with his legs overhanging into the water. Alternatively, he can stand on the hull when it is constructed for this use.

The power unit 14 is mounted recessed into the bull in an aperture 16 extending through the hull between its top surface 18 and its bottom surface 20. The power unit drives a propeller 22 mounted near the back end of the hull to propel the floatboard.

The illustrated power unit 14 employs a small internal combustion engine 24 having a pull starter 26, a spark plug 28 and a fuel tank 30. A carburetor 32, connected to the fuel line leading from the tank 30, receives air from a conduit 34 having an air intake unit 36 at its other end. The exhaust pipe 38 extends laterally from the engine 24 to beyond the hull 12, as seen in FIGURE 1.

The motor shaft 40 is coupled to a gear box 42 mounted behind the engine 24. The impeller 44 (FIGURES 2 and 3) of a bailing pump indicated generally at 46 is secured on the shaft 48 from the gear box. Behind the pump a flexible torque coupling 50 connects the shaft 48 to the drive shaft leading to the propeller 22.

Referring to FIGURES 2 and 3, the engine 24, gear box 42 and pump 46 are mounted in the aperture 16 se cured in a box-like enclosure 52 having a substantially rectangular planar bottom panel 54 and upstanding peripheral rectangular walls 56. The walls 56 protrude upward from the aperture 16 above the top surface 18 of the hull 12 and form a splash guard that blocks water from spilling into the interior of the enclosure. Top covers can also be provided on the enclosure to enhance the appearance and for additional splash protection.

As shown in FIGURE 2, the illustrated enclosure 52 is seated in the aperture 16 inclined several degrees relative to the longitudinal axis 58 of the hull 12. The back edge of the bottom surface 20 of the hull and the front edge of the bottom surface 20 of the hull and the front edge of the bottom panel is considerably above the bottom surface 20. As a result, the enclosure back wall 56a and the back portion of the bottom panel 54 form a sump 60 that is lower than the rest of the enclosure when the board is in the water, even without a user on it.

In particular, when the floatboard is resting in the water under its own weight, as shown in FIGURE 2, the longitudinal axis 58 of the hull is substantially horizontal and hence the bottom panel 54 of the enclosure is inclined downwards forming a small but definite sump in which whatever water is in the enclosure settles. When a user is on the board, the longitudinal axis of the hull inclines to relative to the horizontal and the enclosure bottom panel and back wall form a considerably deeper sump. Thus, whatever water is in the enclosure is elfectively constrained in the back portion, away from the engine 24 and from the carburetor 32.

Further, a cross channel member 62 at the back end of the enclosure52 helps to keep the water in the sump 60 from splashing on the engine when the fioatboard moves unevenly. In particular, as also shown in FIGURE 2, the channel member 62 is preferably disposed with the back flange 62a against the rear wall 56a of theenclosure and with the forward flange 62b serving as a mount for the gear box 42. The channel member is secured through the enclosure bottom panel 54 to a longitudinal channel member 64 (FIGURES 2 and 3) that provides the main structural support for the elements of the power unit 14. Further, the front flange 62b of the channel member 62 generally protrudes above the level of the water in the sump 60 and hence constrains the water in the enclosure from sloshing back and forth.

As indicated above and shown in FIGURES 2 and 3, a bailing pump 46 formed with an impeller 44 housed within a chute 66 is provided at the back of the enclosure 52. The impeller is keyed or otherwise fastened on the shaft 48 to rotate therewith; it is thus disposed to rotate in a substantially vertical plane (FIGURE 2) transverse to the axis 58. The impeller has a plurality of radial vanes 68 (FIGURE 3) that pass close above the channel member web 62c and hence dip into the water in the sump.

As also shown FIGURE 3, the pump chute 66 has a cylindrical portion 66a and a guide portion 66b. The cylindrical portion 66a fits closely around the impeller 44. It is apertured at the bottom to admit water that is in the sump 60. The guide portion 66b extends from the cylindrical portion above and to the side of the impeller; its discharge opening is above the walls of the enclosure 52.

The chute 66 is conveniently secured in place by fastening it to the bottom to the channel member web 62c and to a bracket 70 (FIGURE 2) extending from the back wall 56a of the enclosure.

With further reference to FIGURE 3, the motor 24 drives the impeller clockwise causing it to scoop water from the sump 60 and throw it upward with sufiicient force to expel it from the chute and over the side of the hull 12. The capacity of the bailing pump 46 is readily made sufliciently high to ensure that whatever water splashes and otherwise spills into the enclosure 52 is quickly expelled from it, so that the level of the water in the sump 60 seldom rises above the bottom tips of the impeller vanes 68.

The bailing pump 46, of course, requires no priming and is in no way damaged by continued operation without water in the sump. As a result, it can be directly coupled to the drive linkage between the engine 24 and the propeller 22; no controls or clutching elements are needed to disable the pump when there is no water in the sump 60. Further, the bailing pump 46 is inexpensive and requires essentially no maintenance.

A further feature of the invention is the construction and arrangement of the air intake unit 36 and the conduit 34 leading to the carburetor 32. As shown in FIGURES 2 and 3, the conduit 32 extends upward to well above the hull 12 and its upper end is well inward from the sides of the hull. This positions the intake unit 36 removed from most splashes and spray.

Moreover, the intake unit has a shield 72 secured to the upper end of the conduit 34. The shield is closed at the top, sides and front, and forms an enlarged rearwardly-facing opening for the conduit. Alternatively, the opening can face downward.

An air filter 74 is secured inside the shield 72 filling its rearwardly-facing opening so that all air entering the conduit must pass through the filter. The filter is of a material that relatively freely passes air but blocks'water; polyurethane foam, an open cell plastic, is an example of such a filter material. Further, in the event that the filter becomes clogged with water, no air will pass therethrough and the engine will shut down. In fact, this will occur before the filter 74 becomes fully Wet because as the air supply to the engine is cut down due to water blocking the filter, the fuel-air mixture in the engine will become too rich for the engine to operate. This is desirable to prevent appreciable water from being drawn from the filter into the engine.

Alternatively, the air intake unit 36 can be constructed with an additional length of air conduit connected to the existing conduit 34 in place of the air filter 74 and. shield 72. The additional length of conduit can have a I-shape and be oriented with the crook portion uppermost and the leg portion extending down, parallel to the upstanding portion of the illustrated conduit 34. With the conduit 34 as shown in FIGURE 1, this forms an inverted U- shaped air intake that blocks water from the carburetor. Further, when the additional conduit has sufficient length, the engine will be incapable of drawing water up the additional air conduit in the event water enters its openbottom end. Other shielded air conduit arrangements can also be employed. However, the illustrated arrangement with the water-blocking filter appears most desirable.

In summary, the low cost powered fioatboard described above has a bailing pump that requires no priming, can be driven directly with the means for propelling the fioatboard, and is simply constructed at low cost and so as to require essentially no maintenance. The pump has sufiicient capacity and efiiciency to remove from the engine enclosure whatever water enters therein under essentially any operating conditions. Although described with reference to an internal combustion engine, the bailing pump is equally applicable to a fioatboard or like craft powered with an electric motor.

Further, in accordance with the invention described above, the engine for the fioatboard has an air intake arrangement that is not only shielded from the water, but also incorporates a filter element that blocks water from passing into the air conduit leading'to the carburetor. These features enable the fioatboard to be constructed at unusually low cost. Also, it has small size and light weight. These factors are of particular importance in attaining a powered fioatboard at a sufiiciently low cost to be readily marketable to the vast market of aquatic enthusiasts.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efiiciently attained and, since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A powered aquatic craft comprising:

(A) a substantially solid fioatboard hull having substantially opposed top and'bottom surfaces,

(B) a power-unit for propelling said hull in water,

(C) means forming a recess in said top surface of said hull with said power unit mounted therein fully exposed to the atmosphere, said recess (1) being open so that water can spill into the interior thereof, with said engine being substantially openly exposed to water splashing over said hull, and (2) forming a sump at the lowest point thereof when said craft is floating in a normal operative position, and (D) pump means (1) directly coupled with said power unit and operating whenever said power unit is operating, (2) arranged to pump water from said sump and expel it from said recess. 2. An aquatic craft according to claim 1, wherein: (A) said power unit includes an internal combustion engine having an intake pipe connected directly to said engine for air consumed in combustion of fuel therein, (B) said air intake pipe being arranged to block water from passing therethrough to said engine. 3. An aquatic craft according to claim 1 in which said pump has an impeller rotatable in a substantially vertical plane and disposed with the bottommost portion thereof extending into said sump and arranged to lift water from said sump when so rotated.

4. An aquatic craft according to claim 3 in which:

(A) said power unit includes a shaft that is rotated when said power unit is operative,

(B) said impeller is mounted on said shaft for rotation therewith, and

(C) said pump further comprises a chute enclosing said impeller and arranged to deflect water expelled from said impeller outward from said recess.

5. An aquatic craft comprising:

(A) a substantially solid fioatboard hull having an inclined recess in its upper surface, said inclined recess forming a sump at its lowest point,

(B) an internal combustion engine (1) seated in said recess,

(2) being substantially openly exposed to water splashing over said hull, and

(3) including a rotative shaft terminating in a propeller arranged to propel said craft in water,

(C) an openly exposed impeller attached directly to said shaft for removing water from said sump, and

(D) an air intake unit for delivering air directly to said engine to be consumed in the combustion of fuel therein, said air intake unit having 1) shield means,

( 2) a conduit connecting said shield means directly to said engine, and

(3) a filter element disposed in said shield means to interrupt the passage of air, said filter being an air-pervious, Water-impervious filter.

6. An aquatic craft according to claim 5 in which said filter element is a plastic foam.

7. A powered aquatic craft comprising:

(A) a hull having substantially opposed top and bottom surfaces,

(B) a power unit for propelling said hull in water,

said hull having a longitudinal axis that is substantially horizontal when said craft is afloat with no load thereon,

(C) means forming a recess in said top surface of said hull With said power unit mounted therein fully exposed to the atmosphere, said recess 1) being open so that water can spill into the interior thereof,

(2) having a bottom wall inclined relative to said horizontal axis with the depth of said recess increasing from the front end to the back end thereof so that said bottom wall and a back wall of said recess form a sump when said craft is floating in a normal operative position, and

(D) pump means (1) comprising an impeller rotatable in a substantially vertical plane and disposed with the bottommost portion thereof extending into said sump and arranged to lift water from said sump when so rotated,

(2) directly coupled with said power unit and operating Whenever said power unit is operating, and

(3) arranged to pump water from said sump and expel it from said recess.

8. An aquatic craft according to claim 7 (A) further comprising barrier means extending across said recess between sidewalls thereof and protruding upward from the bottom of said recess and spaced from the back wall thereof, and

(B) in which said impeller is disposed intermediate said barrier means and the back wall of said recess.

9. An aquatic craft comprising:

(A) a substantially solid hull, having substantially opposed top and bottom surfaces,

(B) an internal combustion engine, said engine (1) being mounted in a recess in the top surface of said hull and arranged to propel said craft in water, and

(2) being substantially openly exposed to water splashing over said hull,

(C) an air intake unit connected to said engine for delivering to said engine air consumed in combustion of fuel therein, said air intake unit comprising (1) an air conduit connected directly to and extending upward from said engine,

(2) shield means (a) connected to the top end of said air conduit,

(b) having side and top walls closed to the environment,

(c) having means forming an opening therein, (d) forming an air passage between said opening and said conduit, and (3) an air-pervious, water-impervious filter member disposed in said shield means intermediate said opening and said conduit and interrupting said air passage so as to block the passage of water therethrough to said engine, (D) said recess forming a sump at the lowest point thereof, and (E) a pump coupled to said engine and arranged to pump water from said sump.

References Cited UNITED STATES PATENTS 390,332 10/1888 Andrews 103-96 2,094,136 9/1937 Strawn -70 2,961,967 11/1960 Meyer et al. 103-96 3,171,820 3/1965 Volz 55-528 X MILTON BUCHLER, Primary Examiner. T. M. BLIX, Assistant Examiner. 

